Return to the 36th Chamber

Okay so I've been re watching those movies I enjoy so much but my mandarin must be improving as I'm picking more out, though still not enough to follow the plot (if only I could get Star wars in mandarin!)
During the end of the film he claims to only be using only 40% of his skills and then rapidly increased them. At one point he said (I think) 现在是八十功夫啊 translated as now I'm using 80% of my Kung fu. I thought it would have been something like 现在是百分之八十功夫啊。
Is this a recognised way of shortening percentages when the context is understood? Or did I hear it completely wrong?